Improvement in ventilator-caps



G. KAVANAUGH.

Ventilator Caps.

Inventor: @4J/7K@ x Witnesses:

UNITED STATES PATENT QFFICE.

GERALD KAVANAUGH, OF NEW YORK, N. Y.

IMPROVEMENT IN VENTILATOR-CAPS.

Specification forming part of Letters Patent No. 152,496, dated June 30, 1874; application liled March 28, 1874.

To all whom t may concern:

Be it known that I, GERALD KAVANAUGH, ot' the city, county, and State of New York, have invented a new and useful Improvement in Ventilatorlaps, of which the following is a specification This invention relates to the construction of caps for ventilator' pipes or lines; and consists of pyramidic-shaped and overhanging sections connected with the top ot' the nue, combined witha central section consisting of two pyramids, the bases of which are connected, the sections being supported by means of straps or stays, the construction being hereinafter more fully described.

The drawing is a vertical central section of a ventilator' -cap constructed according to my invention.

Similar letters ot' reference indica-te corresponding parts.

A represents the ventilator flue or pipe. B is the lower section, C is the central section, and D is the upper section. E is a flaring collar or flange on the top of the pipe A, from the inner side of which the central section C is supported by the stays F.

The lower section, B, has a transverse section of an inverted pyramid, G, attached toit, which overhangs the ilange E, a-nd the lower section being of greater diameter than the pipe and flaring llange E, an open annular space, H, is left for the passage of air. The lower section B is supported by the stays I, which are attached to the central section, C, and to the inner side of the section B, as seen at J. More or less in number of these stays may be employed.

The upper section, D, is supported by the stays K from the outside of the section B. The base of the section D overlaps the top ot' section B, leaving an open space, L, for the passage of air between the two.

M is an open space between the central section C and the flange E, and N is an open space between the central section and the section B. O represents the bases of the two pyramids which form the central section C.

It is claimed that this cap will allow a current of' heated impure air to escape, while admitting a current ot' cold fresh air to enter.

It is well known that heated air, as well as smoke and the heated products of combustion, are repelled by the walls ot the dischargeiiue, and ascend in a central column, while cold air will descend the same iiue, by its greater specific gravity, in an annular stratum, thus overcoming the natural draft of the chimney or tlue. This cap is constructed to facilitate this operation, as Well as to exclude rain and prevent sudden gusts of wind from interfering with its operation. This cap may be applied to chimneys as well as to ventilator liues or pipes.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- The combination of pipe A, having the laring collar E, sections B C D, and stays I J K, all constructed and supported in the manner described.

GERALD KAVANAUGH.

Vitnesses:

T. B. MosHER, ALEX. F. ROBERTS. 

